얼굴의 위치를 추적하고 싶을 때는 타원에 중심이 있기 때문에 타원으로 얼굴을 감싸는 것이 좋습니다. 이 중심은 감지된 얼굴의 중심점이기도 합니다. 결과적으로 감지된 얼굴의 위치를 추적하는 것이 더 정확해집니다.
다음 프로그램은 감지된 얼굴의 중심을 추적하여 콘솔 창에 위치를 표시합니다 -
예
#include<iostream> #include<opencv2/highgui/highgui.hpp> #include<opencv2/imgproc/imgproc.hpp> //This header includes definition of 'rectangle()' function// #include<opencv2/objdetect/objdetect.hpp> //This header includes the definition of Cascade Classifier// #include<string> using namespace std; using namespace cv; int main(int argc, char** argv){ Mat image_with_humanface;//Declaring a matrix to load image with human faces// image_with_humanface = imread("person.jpg");//loading an image that contains human face in it// namedWindow("Face Detection");//Declaring an window to show the result// string trained_classifier_location = "C:/opencv/sources/data/haarcascades/haarcascade_frontalface_alt.xml";//Defining the location our XML Trained Classifier in a string// CascadeClassifier faceDetector;//Declaring an object named 'face detector' of CascadeClassifier class// faceDetector.load(trained_classifier_location);//loading the XML trained classifier in the object// vector<Rect>faces;//Declaring a rectangular vector named faces// faceDetector.detectMultiScale(image_with_humanface, faces, 1.1, 4, CASCADE_SCALE_IMAGE,Size(20,20));//Detecting the faces in 'image_with_humanfaces' matrix// for (int i = 0; i < faces.size(); i++){ //Initiating for loop to detect the largest face// Point center(faces[i].x + faces[i].width * 0.5, faces[i].y + faces[i].height * 0.5);//getting the center of the face// ellipse(image_with_humanface, center, Size(faces[i].width * 0.5, faces[i].height * 0.5), 0, 0, 360, Scalar(255, 0, 255), 4, 8, 0);//draw an ellipse on the face// int horizontal = (faces[i].x + faces[i].width * 0.5);//Getting the horizontal value of coordinate// int vertical = (faces[i].y + faces[i].width * 0.5);//Getting the vertical value of coordinate// } cout << "Position of the face is at(x,y)=" << " ("<<CAP_PROP_XI_DECIMATION_HORIZONTAL<<","<<CAP_PROP_XI_DECIMATION_VERTICAL<<")"<< endl;// imshow("Face Detection", image_with_humanface);//Showing the largest face face// waitKey(0);//To wait for keystroke to terminate the program return 0; }
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